Background Mycobacterium avium complex pulmonary disease (MAC-PD) is a chronic lung condition with rapidly increasing prevalence worldwide. Macrolides like azithromycin and clarithromycin are the backbone of long-term antibiotic therapy for progressive MAC-PD. The impact of minimum inhibitory concentrations (MICs), especially within the susceptible range, for macrolides on treatment responses remains unclear. Methods We analyzed adult patients who started treatment for MAC-PD between 1 March 2009 and 1 March 2022 at Seoul National University Hospital. Patients were categorized into four groups according to the clarithromycin MICs of their causative strains at treatment initiation. Logistic regression was employed to evaluate the impact of clarithromycin MICs on the microbiological cure rate. Companion drugs and their MICs, alongside clinical characteristics like age, sex, body mass index, cavity presence, acid-fast bacilli smear positivity, causative species, and erythrocyte sedimentation rate were adjusted in multivariable analysis. Results Four-hundred thirty-six patients (median age, 65 years; 34% men) were included. Microbiological cure rates were 51.8%, 51.9%, 50.0%, and 18.2% for patients with clarithromycin MICs ≤0.5, 1–2, 4–8, and ≥32 µg/mL, respectively (P=0.181). No significant differences in microbiological cure rates were observed across varying levels of clarithromycin MICs within the susceptible range (≤8 µg/mL). Relative to patients with clarithromycin-susceptible strains, patients with MICs ≥32 µg/mL had an odds ratio of 0.25 for achieving microbiological cure (95% confidence interval, 0.06–1.07; P=0.06). Conclusions Treatment responses were comparable among patients with strains having clarithromycin MICs within the susceptible range, but were likely to be worse for patients with strains having MICs ≥32 µg/mL.

中文翻译：

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克拉霉素 MICs 与鸟分枝杆菌复合肺病治疗反应的关系


背景 鸟分枝杆菌复合肺病 （MAC-PD） 是一种慢性肺部疾病，在世界范围内患病率迅速增加。阿奇霉素和克拉霉素等大环内酯类药物是进行性 MAC-PD 长期抗生素治疗的支柱。大环内酯类药物的最低抑菌浓度 （MICs），尤其是在敏感范围内，对治疗反应的影响尚不清楚。方法 我们分析了 2009 年 3 月 1 日至 2022 年 3 月 1 日期间在首尔大学医院开始治疗 MAC-PD 的成年患者。根据治疗开始时致病菌株的克拉霉素 MICs 将患者分为 4 组。采用 Logistic 回归评估克拉霉素 MICs 对微生物治愈率的影响。在多变量分析中调整伴随药物及其 MICs，以及年龄、性别、体重指数、空腔存在、抗酸杆菌涂片阳性、致病菌种和红细胞沉降率等临床特征。结果 共纳入 436 例患者 （中位年龄 65 岁;34% 为男性）。克拉霉素 MICs 患者的微生物治愈率分别为 51.8% 、 51.9% 、 50.0% 和 18.2% ≤分别为 0.5 、 1-2 、 4-8 和 ≥32 μg/mL （P = 0.181）。在易感范围 （≤8 μg/mL） 内，不同水平的克拉霉素 MICs 的微生物治愈率未观察到显著差异。相对于克拉霉素敏感菌株患者，MICs ≥32 μg/mL 患者实现微生物治愈的比值比为 0.25（95% 置信区间，0.06-1.07;P=0.06）。 结论 克拉霉素 MICs 在敏感范围内的菌株患者的治疗反应相当，但 MICs ≥ 32 μg/mL 菌株的患者可能更差。